| 摘要 |
PURPOSE:To prevent the deterioration of efficiency owing to the transmission of a picture by connecting the line of transmission/reception parts when a parameter value is more than a threshold so as to encode/transmit the picture and disconnecting the line when the parameter value is less than the threshold. CONSTITUTION:A threshold circuit 22 compares the parameter value showing the change quantity of a differential picture between a local decoding picture and an input picture with the threshold. When the parameter value is more than the threshold, a transmission command is outputted to a transmission device 10 and gives the instruction of update to a frame update circuit 23. When the device 10 receives the command, it connects the lines of the transmission part and the reception part, and transmits encoding data in buffer memories 5a and 5b. It cuts the line when there is no data. When the parameter value is less than the threshold, the encoding/transmission of the picture is stopped and the local decoding picture is held. Thus, the deterioration of efficiency owing to the encoding/transmission of the differential picture less than the threshold is prevented. |
